大豆异黄酮联合碳酸钙调节去势大鼠骨代谢的研究

[目的]观察大豆异黄酮联合碳酸钙对去势大鼠骨代谢的调节作用。[方法]将60只雌性SD大鼠随机分为6组,分别为假手术组、3个剂量组、碳酸钙组和去卵巢对照组,每组10只。假手术组单纯开腹,其余5组切除双侧卵巢。低、中、高剂量组分别灌胃给予受试物(大豆异黄酮4.8、9.7、29.0 mg/kg BW,碳酸钙25.5、50.9、152.8mg/kg BW),碳酸钙组灌胃给予碳酸钙152.8 mg/kg BW,实验共3个月。每周记录一次体重。实验结束后测定大鼠血清碱性磷酸酶(AKP)和血清钙,取股骨检测股骨中点和远心端骨密度和骨钙含量。[结果]低、中剂量组大鼠股骨远心点骨密度与去卵巢对照组比较显著增加(P﹤0.05),低、高剂量组大鼠股骨骨钙含量与去卵巢对照组比较显著增加(P﹤0.05)。[结论大豆异黄酮联合碳酸钙具有增加去势大鼠骨密度和骨钙含量的作用。     

牛初乳蛋白对大鼠股骨密度的影响研究

目的探讨牛初乳蛋白对去卵巢大鼠骨密度等指标的影响。方法将60只清洁级雌性SD大鼠随机分为假手术组、去卵巢对照组和喂食牛初乳蛋白的去卵巢低、中、高剂量共5组,其中3个剂量组每天分别给予牛初乳蛋白0.20、1.00和2.00g/kgbw连续灌胃12周。检测体重、股骨长度、股骨重量,股骨近心端、中段和远心端骨密度的变化。结果喂食牛初乳蛋白的各剂量组骨密度、股骨重/骨长、股骨重/体重均显著高于模型对照组。结论每天给予0.20mg/kgbw牛初乳蛋白能显著增加去势大鼠股骨近心端、中段和远心端的骨密度。     

增加骨密度类保健食品功能评价方案联合应用的探讨

[目的]合理评价功效成分和补钙成分联合配方保健食品对实验动物增加骨密度功能的影响。[方法]参照《保健食品检验与评价技术规范》（2003版）“增加骨密度功能检验方法”,采用骨密度方案二试验联合钙吸收实验对某保健品进行评价。根据受试物的推荐剂量,设低、中、高三个剂量（0．17、0．33、1．00g／kg）组;在骨密度方案二试验中,,同时设立四个对照组：假手术对照组、去势模型对照组、雌二醇阳性对照组（1．0mg／kg的雌二醇）、碳酸钙对照组,对成年SD雌性大鼠行去势手术后进行试验;在钙吸收实验中,同时设立一个低钙对照组和一个碳酸钙对照组,对断乳SD大鼠进行试验。[结果]骨密度功能检测结果显示：1．00g／kg剂量组去势大鼠的体重增重明显低于模型对照组（P〈0．05）;且该组大鼠股骨远心端和中点骨密度、股骨骨钙含量均明显高于模型对照组（P〈0．05）。钙吸收实验显示：1．00g／ks剂量组大鼠的’体重、身长和表观吸收率均明显大干低钙对照组（P〈0．05）;但该组的这些指标与含钙量相同的碳酸钙对照组相比,差异无统计学意义（P〉0．05）。[结论]通过骨密度试验联合钙吸收实验,认为该保健食品既对去势大鼠有增加骨密度作用,又有补钙作用;联合方法可更全面评价该保健食品的增加骨密度功能。     

牛乳碱性蛋白对雌性大鼠骨密度、骨Ⅰ型胶原特异性氨基酸含量的影响及其氨基酸和蛋白质组成分析

[目的]研究牛乳碱性蛋白(MBP)对正常、去卵巢雌性大鼠骨密度和股骨中骨Ⅰ型胶原特异性氨基酸含量的影响;分析MBP的氨基酸和蛋白质组成特点. [方法]选取104只雌性SD大鼠,其中48只行卵巢切除手术,12只行假手术,其余44只为正常大鼠.将去卵巢大鼠和正常大鼠分别随机分为4组:对照组、低剂量组、中剂量组和高剂量组.各组相应采用0 mg/kg.bw、10 mg/kg.bw、20 mg/kg.bw、30 mg/kg.bw的MBP连续灌胃90 d.实验结束收集股骨,并采用双能X线法检测股骨近心端、中段、远心端骨密度,采用自动氨基酸分析仪法检测股骨中羟脯氨酸和脯氨酸的含量.分别采用自动氨基酸分析仪法和SDS-PAGE电泳法分析MBP的氨基酸和蛋白质组成特点. [结果]10 mg/kg.bw的MBP能够增加正常大鼠股骨远心端的骨密度;MBP能够提高正常低剂量组和去卵巢中剂量组大鼠股骨中羟脯氨酸和脯氨酸的含量. [结论]MBP对正常大鼠骨密度具有增加作用,但不能逆转去卵巢引起的骨丢失;提高骨Ⅰ型胶原特异性氨基酸含量是其作用于骨骼的重要方式;MBP氨基酸和蛋白质组成特点是其作用于骨骼的基础.     

牛乳碱性蛋白对正常和去卵巢大鼠骨代谢的影响

目的探讨牛乳碱性蛋白(MBP)对正常大鼠和去卵巢大鼠骨代谢的影响。方法将60只去除卵巢雌性SD大鼠随机分为假手术、去卵巢对照以及去卵巢低、中、高剂量5组;将另外44只正常雌性SD大鼠随机分为正常对照、正常低、中、高剂量4组。分别采用10、20、30mg/kgbwMBP给大鼠连续灌胃90d,检测股骨近心端、中段和远心端骨密度,同时检测股骨中Ca、Mg、P等矿物元素含量。结果正常低剂量组大鼠股骨远心端骨密度显著高于正常对照组;而各剂量MBP对去卵巢大鼠的骨密度无显著作用;正常各组之间以及去卵巢组之间比较,骨矿物质含量虽无统计学差异,但可以观察到其水平上的上升趋势。结论10mg/kg.bw的MBP能提高正常生理状态下的峰值骨密度,以股骨远心端效果最好,但未见MBP对去卵巢大鼠骨密度的影响。MBP除影响骨骼中矿物元素含量外,还可能通过其他方式作用于骨代谢。     

牛乳碱性蛋白对大鼠骨密度的影响

目的探讨牛乳碱性蛋白(MBP)对正常和去卵巢大鼠骨密度、血液生化指标的影响。方法将60只雌性SD大鼠随机分为假手术、去卵巢对照和去卵巢低、中、高5个剂量组;另将44只正常雌性SD大鼠随机分为正常对照、正常低、中、高4个剂量组。分别采用10、20和30mg/(kg.d)MBP给大鼠灌胃连续90天,检测股骨重量,股骨近心端、中段和远心端骨密度与骨矿含量的变化,检测血清总蛋白、胆固醇和血糖等7项血液生化指标。结果正常低剂量组大鼠股骨远心端骨密度和骨矿物质含量显著高于正常对照组;各剂量MBP对去卵巢大鼠骨密度无显著作用;正常低、高剂量组大鼠血清总蛋白和白蛋白显著高于正常对照组。结论10mg/(kg.d)的MBP能显著增加正常大鼠股骨远心端骨密度,对去卵巢大鼠骨密度和骨矿含量无影响,血清总蛋白和白蛋白同时明显升高。     

淫羊藿、杜仲对卵巢切除大鼠骨密度和骨钙含量的影响

目的探讨淫羊藿、杜仲对卵巢切除大鼠骨密度和骨钙含量的影响。方法取SPF级雌性SD大鼠60只,切除卵巢建立大鼠骨密度低下模型后随机分成6组:淫羊藿和杜仲低、中、高剂量组(g/kg·bw)0.15、0.30、0.90,碳酸钙和溶剂对照组,假手术组。统一用低钙饲料和相应受试物灌胃3个月后,处死大鼠,测定其体重、股骨中心和远心端骨密度和骨钙等含量。结果假手术组大鼠末期体重及增重低于溶剂对照组,股骨中心、远心端骨密度和重量、骨钙含量高于溶剂对照组;高剂量组(0.90g/kg·bw)大鼠骨钙含量、股骨中心和远心端骨密度高于溶剂对照组,中、高剂量组大鼠股骨中心、远心端骨密度和重量、骨钙含量比碳酸钙对照组高,但未达显著性水平。结论淫羊藿和杜仲能增加卵巢切除大鼠骨密度和骨钙含量,对雌激素缺乏诱发的骨钙丢失有抑制作用。     

基准剂量法在突发性镉污染饮用水应急阈值研究中的应用

目的应用基准剂量法(BMD)探讨突发性镉污染饮用水应急阈值。方法将40只健康4周龄SPF级雄性SD大鼠按体重随机分为4组,分别为对照(纯净水)组和11.42、7.62、5.07 mg/kg氯化镉染毒组,每组10只。采用灌胃方式进行染毒,染毒容量为10 ml/kg,每天1次,连续4周。测定股骨重量、骨钙含量、骨密度。采用BMD 2.7版软件包计算BMD及其95%CI下限值(BMDL)。结果与对照组相比,各剂量氯化镉染毒组大鼠的股骨质量、骨钙含量均下降(P0.05),7.62mg/kg氯化镉染毒组大鼠的股骨中点骨密度及11.42 mg/kg氯化镉染毒组大鼠的股骨远端骨密度也降低,差异均有统计学意义(P0.05)。BMD软件模型拟合最佳BMDL值为1.22 mg/kg;以此为参考,计算突发性水污染饮用水镉应急阈值为0.02 mg/L。结论本研究采用BMD法计算得出的突发性水污染饮用水镉应急阈值,可为国内镉突发性水污染事件的风险评估提供科学依据。     

乳清蛋白肽对骨密度和骨钙含量的影响

目的利用胰蛋白酶水解乳清蛋白制备促钙吸收肽,研究乳清蛋白肽对生长期小鼠骨密度的影响。方法选用ICR小鼠,按体重随机分成低钙组、补钙组、正常组和样品组,样品组以灌胃方式给予钙和乳清蛋白水解肽。4w后处死,取小鼠双侧股骨湿重、干重、长度和股骨指数。结果含肽低、高剂量组的股骨长度分别为16.62±0.39和16.97±0.29 mm,均显著(P0.05)大于低钙对照组16.36±0.41mm;含肽低、高剂量组小鼠股骨密度分别为1.417±0.044和1.429±0.042 g/cm3,显著(P0.05)或极显著(P0.01)大于低钙对照组1.335±0.122 g/cm3;含肽高剂量组小鼠的股骨干重为0.0666±0.0042g,显著(P0.05)大于低钙对照组(0.0536±0.0022)和补钙组0.0596±0.0052 g;含肽低剂量组小鼠的股骨钙含量为221.16±6.24 mg/g显著(P0.05)大于低钙对照组213.46±12.65 mg/g;含肽高剂量组的股骨钙含量为228.55±5.18 mg/g极显著(P0.01)大于低钙对照组213.46±12.65 mg/g和补钙组215.32±15.72 mg/g。结论乳清蛋白水解肽对钙吸收有显著促进作用,并具有剂量效应。     

长期饮用牛奶对雄性大鼠生殖功能的影响

目的 通过2代繁殖实验研究长期饮用牛奶对雄性大鼠生殖功能的影响.方法 牛奶组及对照组4周龄SD大鼠,雌雄各20只.牛奶组饲喂牛奶组饲料和市售纯牛奶,对照组饲喂对照组饲料.实验开始10周后合笼,产下子一代（F1）和子二代（F2）后处死雄性大鼠,分别记录雄性大鼠生长发育情况、精子水平、激素水平、子代活产数等指标.结果 亲代牛奶组雄鼠血液中促黄体生成激素（LH）（0.43±0.17）U/L低于对照组（0.72±0.26）U/L,子二代F2b活产数对照组（17.00±2.94）只高于牛奶组（13.10±3.57）只,亲代牛奶组大鼠体重在第12周（476.62±38.70）g低于对照组（515.37±37.59）g,差异均有统计学意义;各器官的脏器系数、精子和生育相关指标在两代的两组间差异均无统计学意义.结论 未发现长期饮用牛奶对雄性大鼠生殖功能有明显影响,牛奶对亲、子代体内激素水平和子代活产数的作用有待进一步确认.     

白藜芦醇对去卵巢大鼠骨密度的影响

目的:探讨白藜芦醇(RES)对去卵巢大鼠骨密度(BMD)的影响。方法:48只SD大鼠随机分为6组,分别接受假手术(A)、去卵巢(B)、去卵巢+0.03mg/(kgbw·d)己烯雌酚(DES,C)、去卵巢+RES5、15和45mg/(kgbw·d)(D,E,F)90d后,用双能X线吸收法测定大鼠的骨密度,观察其改变。结果:B组大鼠各BMD测定指标均显著低于A组,D、E、F组全身和腰椎BMD均显著高于B组,E、F组整体股骨BMD显著高于B组。结论:白藜芦醇对去卵巢大鼠的骨丢失有抑制作用,以45mg/(kgbw·d)剂量对骨密度的保护效果最好。     

两个新的钙感觉受体基因多态性与中国男性骨密度相关性研究

目的研究钙感觉受体(CaSR)基因两个新位点多态性与中国男性骨密度的关系。方法采用双能X线吸收仪对374名研究对象进行腰椎及股骨扫描，应用PCR-RFLP方法检测CaSR基因R990G和E1011Q两个多态位点基因型，用广义线性模型分析CaSR基因多态性与第2～4腰椎及股骨骨密度关系。结果在调整环境危险因素前后，均未发现CaSR基因的两个位点多态性与男性股骨颈、股骨柄和股骨三角区及第2～4腰椎的骨密度相关。结论在中国男性人群中CaSR基因R990C；和E1011Q位点多态性与股骨及腰椎骨密度无显著性相关。     

膳食钙摄入量与青春前期女童骨量关系的研究

目的:研究青春前期女童膳食钙摄入量与骨量的关系,为指导合理钙营养提供科学依据。方法:采用双能X线骨密度测量仪测量年龄在10±1岁的194名青春前期女童全身及多位点骨密度和骨矿物质含量,采用食物频数及3d膳食询问法调查膳食钙摄入量,问卷法调查体力活动。结果:日均钙摄入量与所测各位点骨矿物质含量及骨密度均呈显著正相关;日均钙摄入量平均从257mg增加到759mg,不同位点的骨矿物质含量和骨密度分别增加13%～22%和3.6%～16%。结论:增加青春前期女童膳食钙摄入量有助于获得较高骨量和骨密度。     

Effects of body mass index on bone mineral density in men

INTRODUCTION: A strong positive association between body mass index and bone mineral density is well defined in postmenopausal osteoporosis, but not in men. AIMS: The primary goal of the current research was to investigate this association in case of men. METHODS: According to WHO criteria (T-score below -1.0 at all measure site) seventy-two (mean age 55.7 +/- 0.99, range 38-78 yr normal density) healthy male with normal density were recruited. Exclusion criteria were the absence of any risk factors or signs of metabolic disease. Bone mineral measurements at the lumbar spine (L2-4) and femoral neck were performed by the dual-energy X-ray absorptiometry (DEXA, Lunar DPX-L, USA), bone mineral content of the non-dominant radius was measured with single photon absorptiometry (SPA, NK-364, Hungary). Participants were divided into three groups according to body mass index normal weight (18.5-24.9 kg/m2), moderate overweight (25-29.9 kg/m2) and obese subjects (> 30 kg/m2). RESULTS: Femur neck density was significantly lower in the normal weight than in the overweight counterparts (0.969 +/- 0.03 vs 1.062 +/- 0.02 p = 0.01). There was a strong positive association between BMI and femur neck BMD (r = 0.412 p < 0.001). Body mass was an independent predictor of femur neck bone mineral density (regression coefficients 0.382, p = 0.001). There was not correlation at the lumbar spine and the radius sites. CONCLUSION: Bone density at femur neck sites is lower in the normal weight men than in obese subjects, therefore the risk factors for proximal femur osteoporosis are higher in these cases. Prevention strategy is needed for men in the lowest quintile of body mass to prevent further decrease in BMD and reduce the risk of hip fracture.     

Isoflavone-rich soy protein isolate attenuates bone loss in the lumbar spine of perimenopausal women

BACKGROUND: No published studies have directly examined the effect of soy protein with isoflavones on bone or bone turnover in perimenopausal women. OBJECTIVE: Our objective was to determine the effects of 24 wk of consumption of soy protein isolate with isoflavones (80.4 mg/d) in attenuating bone loss during the menopausal transition. DESIGN: Perimenopausal subjects were randomly assigned, double blind, to treatment: isoflavone-rich soy (SPI+; n = 24), isoflavone-poor soy (SPI-; n = 24), or whey (control; n = 21) protein. At baseline and posttreatment, lumbar spine bone mineral density (BMD) and bone mineral content (BMC) were measured by using dual-energy X-ray absorptiometry. At baseline, midtreatment, and posttreatment, urinary N:-telopeptides and serum bone-specific alkaline phosphatase (BAP) were measured. RESULTS: The percentage change in lumbar spine BMD and BMC, respectively, did not differ from zero in the SPI+ or SPI- groups, but loss occurred in the control group (-1.28%, P: = 0.0041; -1.73%, P: = 0.0037). By regression analysis, SPI+ treatment had a positive effect on change in BMD (5.6%; P: = 0.023) and BMC (10.1%; P: = 0.0032). Baseline BMD and BMC (P: < or = 0.0001) negatively affected the percentage change in their respective models; baseline body weight (P: = 0.0036) and bone-free lean weight (P: = 0.016) contributed positively to percentage change in BMD and BMC, respectively. Serum BAP posttreatment was negatively related to percentage change in BMD (P: = 0.0016) and BMC (P: = 0.019). Contrast coding using analyses of covariance with BMD or BMC as the outcome showed that isoflavones, not soy protein, exerted the effect. CONCLUSION: Soy isoflavones attenuated bone loss from the lumbar spine in perimenopausal women.     

Dietary iron positively influences bone mineral density in postmenopausal women on hormone replacement therapy

The associations of dietary intakes of iron and calcium on change in bone mineral density (BMD) were examined over 1 y in healthy nonsmoking postmenopausal women (mean age 55.6 +/- 4.6 y) stratified by hormone replacement therapy (HRT) use (HRT, n = 116; no HRT, n = 112). BMD was measured at lumbar spine L(2)-L(4), trochanter, femur neck, Ward's triangle, and total body using dual-energy X-ray absorptiometry at baseline and 1 y. Mean nutrient intakes were assessed using 8-d diet records. All women received 800 mg/d of supplemental elemental calcium. Regression analyses examined the effects of iron and calcium intakes on BMD change adjusting for years past menopause, baseline BMD, weight change, exercise, and energy intake. The interaction of iron with calcium on BMD change was assessed using tertiles of iron and calcium intake and estimated marginal mean change in BMD. Iron was associated (P < or = 0.05) with greater positive BMD change at the trochanter and Ward's triangle in women using HRT. Calcium was associated (P < or = 0.05) with BMD change at the trochanter and femur neck for women not using HRT. In women using HRT in the lowest tertile of calcium intake, change in femur neck BMD increased linearly as iron intake increased. In women not using HRT, BMD increased in the women in the highest tertile of calcium intake. We conclude that HRT use appears to influence the associations of iron and calcium on change in BMD.     

Protein consumption is an important predictor of lower limb bone mass in elderly women

BACKGROUND: The effect of protein intake on bone density is uncertain, and evidence exists for beneficial effects of both low and high protein intakes. OBJECTIVE: The objective was to study the relation between protein consumption and bone mass in elderly women with allowance for other lifestyle factors affecting bone metabolism. DESIGN: We conducted a cross-sectional and longitudinal study of a population-based sample of 1077 women aged 75 +/- 3 y. At baseline, protein consumption was measured with a food-frequency questionnaire, and bone mass and structure were measured by using quantitative ultrasound of the heel. One year later, hip bone mineral density (BMD) was measured by using dual-energy X-ray absorptiometry. RESULTS: Subjects consumed a mean (+/-SD) of 80.5 +/- 27.8 g protein/d (1.19 +/- 0.44 g protein/kg body wt). Regression analysis showed a positive correlation between protein intake and qualitative ultrasound of the heel and BMD after adjustment for age, body mass index, and other nutrients. The dose-response effect was best characterized by protein consumption expressed in tertiles, such that subjects in the lowest tertile (<66 g protein/d) had significantly lower qualitative ultrasound of the heel (1.3%) and hip BMD (2.6%) than did the subjects in the higher tertiles (>87 g protein/d). CONCLUSION: These data suggest that protein intakes for elderly women above current recommendations may be necessary to optimize bone mass.     

发育期雌性大鼠VitD缺乏对去卵巢后骨质的影响

【目的】　探讨大鼠在生长期VitD缺乏对去卵巢后骨密度 (BMD)的影响。　【方法】　用 2 1天龄雌性SD大鼠 42只分为正常对照组和佝偻病模型组 ,并对佝偻病组采用不同的治疗方法。于大鼠 5月龄时 ,全部施以双侧卵巢切除术 (OVX) ,分别在佝偻病期、佝偻病治疗后期、卵巢切除后对所有大鼠进行腰椎BMD检测。　【结果】　佝偻病大鼠腰椎BMD较正常对照组低 (P <0 .0 0 1)。鼠 (OVX)后腰椎BMD下降 ,佝偻病组较正常对照组低 (P <0 .0 5 )。　【结论】　雌性大鼠在生长期VitD缺乏对去势后骨质疏松有不利影响